Alfred bogisoh



UNITE STATES ALFRED BOGISCI-I, OF FEUERBACH, GERMANY, ASSIGNOR TO J. I'IAUFF &

PATENT OFFICE.

(30., GESELLSCHAFT MIT BESCHRANKTER HAFTUNG, OF SAME PLACE.

PHOTOGRAPHIC DEVELOPER AND PROCESS OF DEVELOPING.

SPECIFICATION forming part of Letters Patent No. 615,792, dated December 189 Application filed July 20, 1898. Serial No. 686,406. (No specimens.)

O -I.1 hydroquinone of the constitution O II OHAE are distinguished by the fact that they develop quickly and very powerfully. and are only in the slightest degree affected by the temperature. They are thus capable of excellent service in instantaneous photography and in the studio or laboratory. These halogen substitution products are used according to the following example: Water, one hundred cubic centimeters; monochlorhydroquinone, one gram; crystallized sodium sulfite,

eight grams; potassium carbonate or dry s0 dium carbonate, four grams; potassium bro-- mid, 1:10, ten to twenty drops.

Having thus described my invention, I claim as new and desire to secure by Letters Patent 1. The process herein described of developing the photographic image on sensitized plates, which consists in subjecting the sensitized plates to the action of a solution of the halogen substitution products of dioxybenzenes, substantially as set forth.

2. A developing solution for photographic negatives, composed of an alkaline, aqueous solution of the halogen substitution products of dioxybenzenes, substantially as set forth.

In testimony that I claim the foregoing as my invention I have signed myname in presence of two subscribing Witnesses.

ALFRED BOGISOH.

Witnesses ERNST DIETRICH, WM. HAHN. 

